Method of and apparatus for production of foam solutions



Nov. 11, 1930. J A, MCCRACKEN 1,781,294

METHOD OF AND APPARATUS FOR PRODUCTION OF FOAM SOLUTIONS Fi led Sept. 28, 1927 IN VE' NTOR CIT Patented Nov. 11, 1930 STATES harem oFFicE;

JAMES A. MoCRACKEN, or LOS ANGELES, CALIFORNIA METHZOD GF AND APPARATUS FOR PRODUCTEON 0F FOAM SOLUTIONS Application fileclifieptember 28, 1927. Serial No. 222,637.

production.

e The manner of extinguishingfires with foam is well known and understood. It consists in applyingto the burning surface or liquida froth produced by intermixing solutions (or) aluminum sulfate (6) sodium bicarbonate and a stabilizing agent such as licorice. On mixing these solutionscarbon dioxidis set free, aluminum hydrate is precipitated in gelatinous form, and the licorice acting to increase thesurface tension of the liquid, a erydense andpermanent froth consistingsuhstantially of water and having a high value for extinguishing fires is produced. This foam is flowed or sprayed over the surfaces of burning liquids, and is plas tered over burning wood by ejection under pressure through a nozzle. V I The chemlcals above described are hereinafter referred to as foam producing agents,

or simply as. agents,and when reference is made to an agent it will be understood that I refer to. either the (a) or the (1)) chemical above, While if the referenceis to agents in the plural it will be understood that one of the agents referredto is the chemical.

and the other the. (7)) chemical, by the coinbination of which the desired foam is. produced. j y l 2 In the system in most general use it has been the practice to prepare the two solutions inadvance, storethem until required for use,

and conduct them to the. seat of the 'fire through separate pipe lines underthe pressure generatedibypumpjs located near the left standing in lines will put them out of commission. Both solutions depreciate some- What on standing and must be checked and restandardized, and the pumps tested at frequent intervals. I

As the solutions are bulky a large amount of storage (half of which must be lead lined) must be provided for the protection of a risl; such as an oil refinery. In addition there must be a complete system ofidouble pipe lines extending to all parts of the area to be protected. Attempts to mix the solutions near the storage plant and conductthe foam through a single line have not been success ful, owing to the breaking down of the foam by friction in transit. The storage and pipe line system heretofore used, While inmost cases quite efficient, has therefore. provone ztravagantlyexpensive to install and to keep in operating condition. y 1 A type of portable extinguishers has heretofore been used, comprising tanks for the chemicals and pumps for forcing them to the point of intermixture, but such portable units, even When mounted on motor trucks,

have had a verylimited capacity, because of the great Weight of Water tobe transported, the total solution consisting substantially of one. part by weight of active chemical to eight parts by Weight of water. Thus a portable unit having a net Weight of ten tons (a Verylarge size) would consist of about oneton machinery and tanks, eight tons Water and one ton actual fire extinguishing material.

By the use of my present invention the entire standing system of storage tanks and pipe lines may be done awaywith and an unlimited quantity of foam produced, continuously, by the use of a portable unit Weighing only a few hundred pounds. The only requisite is a supply of Water under pressure in the general icinity ofthe point at Which the portable unit isto be spotted, such supply being usually already available.

My invention comprises a method andan. apparatus by ,meansfof which the dry powdered chemicals can be separately brought intosolution in flow streams of Water, by means of the pressure on thewater system I and without the use of pumps or other ma- Referring to Figures 1 and 2,1 is a cylin der having a tight head 2 into which is permanently fixed the water pipe 3, controlled by the valve 8 and communicating through aflexible connection with a supply of water under pressure not shown. 4.4c are small perforations-through the wallof this pipe close to the under side of the head. The

area and purpose of these perforations will hereinafter appear.

' 55 are trunnions attached to the cylin der, on its diametric' line andrat the center or gravity, on which the cylinder is carried engagement ofthe lugs 9-9 with 7 made fast to the frame. y i. V wThe bottom 11 of .the cylinder should be in, the b earingsG supported by the legs 7. The cylinder thus supported may be inverted' byrevolving it.on the trunnions. .The

water supply tothe valve 8 must bethrough v over this plate rapidly dissolves it away at 'a flexible connection, as a hose.

' The cylinder -may be held in a vertical position, either upright or inverted, by the a lug 10 readily detachable. and may be revolved by means of the lugs 12and held inHposit-ion by a screw thread or bythe bayonet catch .indicated'at 13. Toprevent leakage a ring ofsheet packing 141 may be inserted;

In the bottomofthe lower head 11 is'fixed a pipe nipple-15 through which solution is Qdischarged from thecylinder, and which may communicate with the solution-mixing head through a flexible line, as a hose length with a pipe extension if" required.

. .width' of which maybe from to ac-' cordingto the'size of the. apparatus In To the lower head is rigidly fixed h plate 16 which .maybe supported in any convenient manner, as by the studs 17 This plate should'conform to the'shape of the cylinder,

leaving arestricted annular opening 18 the general terms the-area of thisannular open- I mgqmay approxlmate the inside'area'of rum 3-.

*The, lower end pipe 3 is. brought down close to the plate, leaving a gap. 19 between the plate and the carefully vsquared en'd of pipe 3..;The areaof this opening may pref,-

erably be approximately one-half the inside cross sectional.- area of the J pipe The ob} ect' of this gap is to, project asheet of water at a relatively high velocity over the plate,

which requires that the pipe area'be somewater supply shut ofi atvalve 8, itis. in

be on top) is removed, leaving the connections 15 attachedthereto; The upper head 2 of the shell will now be at the bottom'w'ith the water "pipe 3 projecting upward therefrom,.while the plate 16,.being attached to the bottom plate 11, will be out oftheway and the cylinder open at' the end which is then uppermost.

. verted fromthe operatingposition shown in 1 Figure 1, and the bottom 11 (which wlll then 7 V Intothe cylinder and art'mndv pipe 3 isnow I poured a sufiicient quantity ofpowdered (a) or (Z2) chemical to fill it to say of its capacity. 'The cap 11 is then replaced, the

water turned on and, the'cylinder again in-- the bottom, the solution passing downward throughthe annular opening 18 and underneath. the plate 16 into the outlet connection 15. Solution proceeds, at an even rate'unti-l theentire batch of power is thus dissolved and carried away, this rate increasing or decreasing as the supply offwater isincreased or decreased." By feeding water at apredetermined ratethe production of'solution may be controlled as desired;

Therate of solution may also be varied by varying the area of theg'ap 19, as-byadvancing the lower end of pipe 3 toward or with- ]drawing it from plate 16-,bymeans of the" threaded portion SQQt-he pipe collar 4O and the union41.-,,The wider, this gap and the lution and the more dilute 'thesolution produced. "Anadjustment may readily be found at which exactly the required amount-of walower the velocity of the water sheet issuing therefrom, the slower will be the rate of so- The purpose ofithe perforations indicatedh,

at 4 in Figure 1 is to prevent'bridging of the. V '7 powdered material and vto force itdownwardb ontoplate The pressure inside pipe 3 being necessarilygreater than the pressure in q the lower portion of the :shell=;(which dis-, charges into a substantially open end) water j flowing out of these .perforations forms a waterpiston by which theplugof powder is forced downward as'consumed. The areaof these perforations may be substantially oneseventh of the area. or the pipe, butthisv area is of minor importance as no moreiwater can escape from these holes than is requiredto ll: the shell above the powder, a very small part of the quantity required to bring it into solutions The use of these perforations is optional and they may be omitted if preferred. The apparatus illustrated in Figures 3 and t is designed to produce the two-solutions simultaneously; Bythe alternate use of. a pair of suchunits two continuous streams of solutionimaybeproduced with a single water inlet-and a single outlet for each solution, withontthe-use of any hand operated valves. As the general construction and functioning of this apparatus are covered by the above description, only the points. of diflerencewill be described. 1

Referring to Figures 3 and 4, water under pressure from a source not shown 1 passes through the brokenpipe 20 into the branch lines2l and22. The two shells of which this unit is composed are identical in construction and operation, and only one side need be described. r j

WVater passing though pipe 21 enters the ca .23 of the trunnion bearin 22 which is cored out to register with a cored hole 24 in the trunnion 25when the shell 26 is in the operating position shown. These holes do not register when the shell is inverted, and the trunnion and its cap thus form a valve thr ugh which water can pass only when the shell 1s 1n the upright or operating posit on.

The cormg 1n the trunnion 1s continued 1n- Kvardly and communicates with a cored hole 27 extending upwardly thorugh a rib 28 formed in the adjacent side of the shell. This cored hole is carried through the wall of the rib as at 29 and into the opening thus formed is fastened a pipe nipple 30 communicating though an L 31 with a pipe3 which isidentical with the pipe of the same number shown in Figure 1.

On the opposite side of the shell is formed 7 the rib 32 which terminates a short distance above the bottom head .11. Through this rib is cored a passage 33 communicating with a cored hole 34: passing part way through the trunnion 35 and registering with a similar hole 36 formed in the supporting leg 37 and terminating in a screw threaded pipe connection indicated at 38. A solution conductor,

not shown is to be attached to this connection and it will be noted that the valve formed by the opposed openingsin the trunnion and leg is open only when the shell is in operating position and is closed when the shell is inverted for rechargingthus preventing a return flow of solut on 1n case two unlts have their corresponding discharges connected to a single conductor line. The cored passages 27. and 33 may be replaced by pipes or tubing if preferred.

On inverting theshell and removing the bottom plate 11 for recharging, the shell will be full of water, which. must be removed prior to adding the powder. This may be done by tipping the shell to a horizontal position which will allow the water to flow out without bringing the trunnion ports into registry and thereby admitting more water.

While I have described a particular form of apparatus suitable for dissolving a charge of foam producing agent under pressure,it will be obvious that substantially the same results may be obtained by means ofmodifications of this apparatus entirely within the scope of my invention;

The details shown refer toa preferredconstruction only, and that which I have invented and wish to claim as broadly as the stateof the art will permit is set forth and defined solely inthe attached claims.

I claim as my invention: a

1. The method of bringing a foam pro ducing agent into solution, which comprises: producing a flow stream of water under pres sure; converting said flow stream into a sheet of flowing water under pressure; superposing on said water sheet a body of foam producing agent; forcing said superposedbody into continued contact with said water sheet by admitting water under pressure on top 01" said body; producing a solution of said agent sub stantially on the plane of contact between said body and said water sheet, and collectingsaid solution into a flow stream. 1

2. Themethod of bringing'a foam producing agent into solution, which comprises: producing a' flow stream of water under pressure; converting said flowstream into a sheet of flowing water under pressure; superposing on said water sheet a body of comminntcd foam producing agent; producing a solution of saidagent substantially ontheplane of contact between said body and said water sheet, and collectingsaid solutions into aflow stream;

3. An apparatus for dissolving a foam pro ducing agent comprising, a vessel with vertical cylindrica-lwalls and with oneend perma-' nently closed, said vessel beingsupported on trunnions so asto render it readily reversible end for end; a readily detachable closure for theend oppositethe fixed end; a plate attached to said closure, inside said vessel, in a position close tosaid closure and at a right angle to thevertical axis of said vessel; said plate being of such size as to leave a narrow annular opening between said plate and said cylindrical walls; apipe for admitting water under pressure into said vessel, saidpipe terminating atsuch distance from said plate as to leave a relatively narrow gap therebetween, said pipe being further provided with a means for the escape of water inside said vesseland close to the fixedend thereof; a means for conducting water into said pipe,

under pressure, and at, its inner end with =means interior. too sai'dvessel, for, conand a conductor forjdischarging solution communicating with the interior ;of, said vessel. 1 V 1 4. An apparatus for simultaneously dissolving two foam producing agent-s, com.- prising: a pair of dissolving vessels each substantially as described in claim 3, ,trunnions of said vessels being so interconnected as to sels.

cause theinversion of one of said Vessels to simultaneously invertlthe other of said ves- 5. An apparatus for dissolving a foam'producing agent, comprising: a substantially closed vessel, the lower end of said-vessel consisting of a readilydetachableclosure; a plate horizontally supported in said vessel near the lower end thereof; a passage between said plate and the wall of said veseslg a'pipe for-admittingwater under pressure.

into said vessel and terminating close to said plate, leaving anarrow spacebet-ween said plate 'andlthe end of said pipe; an opening through the'wall of said pipe near theupper end -:of said vessel; .means for conducting water under pressure into said pipe, and means: communicating with said vessel 'at a point substantially below said plate for con-v ducting liquid but of 1 said, vessel.

i 6.An apparatusfor simultaneously dissolvlng twofoamyproducing agents,"compr1sing: a palr of dissolving vessels each sub:

in claimT-7 in which, the. passages-formed througheach bearing-and its corresponding trunnion are so located as; to be out of register and closed to the passage of liquid when the vessel of which said trunnion is a part is in that position at which the closure isuppermost, and in register and open to the passage of liquid when said vesselis inverted from said Josition. f f f 1 9. ilhe continuous method of bringing a foam producing agent into solution which comprises: projecting a flow stream of water against asubstantially horizontal surface to a convert said flowstream into-a substantially horizontal sheet of flowing water, and superposing on said water sheet a body of said agent in ,comminuted form 10. An apparatus: for continuously dissolvinga foam producing agent, comprising:

means for producing a sheet-of horizontally JAMES ainooaAounn. I

stantially' as described in claim 5, trunnions 1 forfsaid vessels, said trunnionsbeing so connected asto cause the inversion of'oneof said vessels tozsimultan'eousl'y invert the-other of said vessels. 1

V7. 'Anapparatu's'for simultaneously pro- M ducing'solutions of two foam producing agents from bodies of solid comminuted agent,icomprising: two substantially closed I vessels each provided with means for intro- 1 ducing; 'a-body of. saidrcomminuted solid agent, said vessels being supported by trun- 1 nions resting'intrunnion bearings, said: vessels beingsointerconnected as to be simultaneouslyinversible-fl end 7 for: end on? said trunnions; a passage formed through onetrunnion and bearing on each said yes- 7 .sel,f; said passage communicating at its outer end withasource of supply of i Water 1 vertinga fiowistreaim of Waterintoa sheetfofflowingwater, said sheetflbeing so positifonedinside saidvesselias to underlie and contact with said body of, agent for bringing "said agent, into solution; and a passage formed through the oppositer'trunnio'nand bearing on each vesselfsaido passage-communic'ating with the interior vof said vessel beneath said waterisheetandiwith means ex; terior, to saidvessel for smparatelyconductv ing the solutions produced in the twosaidf vessels: to apointeof: intermixture thereof. i

apparatus substantially asdefi'ned'i 

